Federal energy regulators will allow Pacific Power to continue operating the Wallowa Falls hydro project for the next 40 years, while also requiring additional protections for bull trout in the Wallowa River.
The facility, located south of Joseph near Wallowa Lake, consists of a dam on the river’s east fork that diverts water to a small powerhouse with a single 1.1-megawatt generator capable or producing enough electricity for about 500 homes.
Pacific Power has run the system since 1942 when it acquired the original operating license from Inland Power and Light. On Tuesday, the company announced it received a new license from the Federal Energy Regulatory Commission after the previous license expired last year.
As part of the agreement, project manager Russ Howison with PacifiCorp said they will invest $3 million over the next three years to improve stream flow and habitat for bull trout, which are now listed as threatened in Oregon under the Endangered Species Act.
“Environmental standards have changed so much,” Howison said. “With an old operating license, you have to bring the project up to new environmental standards.”
Most of the work will involve leaving more water in stream for fish, and blocking passage into areas where bull trout may be vulnerable, Howison said.
In previous years, Howison said the minimum in-stream releases from the dam into the river bypass were just half a cubic foot per second. Those figures have since bumped up significantly to 4 cubic feet per second during the winter, and five cubic feet per second during the summer, with one cubic foot of water equal to roughly 7.5 gallons.
“That’s putting considerably more water in the portion of the stream below the dam,” he said.
Howison said they are working with the U.S. Geological Survey install a real-time stream gage to monitor required minimum flows on the East Fork Wallowa River. The dam’s intake structure will be modified to account for additional releases.
Crews will also build a fish passage barrier leading into the tailrace below the powerhouse, which had attracted bull trout especially during the summer. The problem, Howison said, is when the dam faces an unplanned outage, and the tailrace is suddenly drained of water.
“That’s the real risk to bull trout,” he said.
Since the project is right next to a number of popular hiking and snowshoeing trails, Pacific Power has agreed to work with the Forest Service on putting in new signs and landscaping to conceal the powerhouse for visitors. Once the work begins, Howison said there may be some temporary access restrictions, though the company will notify neighbors if and when that happens.
Contact George Plaven at email@example.com or 541-966-0825.